wiring for 240Z wiper relay

[Guest jeodellx]

I was hoping to get some help on wiring my 73 240Z wiper relay. There are a few single wires that can be plugged into the relay and a couple of them are the same color. Previous owner had added an electric fuel pump and it looks like there are at least two extra relays on the bracket under the glove box. Currently I have slow and fast wiper speed, but no intermittent and if you turn the switch off the wipers just stop instead of continuing to the lowest position.

 

Thanks for the help

[Dragonfly]

With your car being a 73' I could be wrong on this but I believe that your car only has "off", "slow" and "fast" for the wipers, as for the wipers not returning to the park position that has to do with your wiper motor not a relay under the dash. Unless you feel like a little torture and getting the oportunity to shed some blood, sweat and tears (as well as curse words) on the car just practice turning off the key when the wipers are where you want them. You can also do a search for using the Honda wiper motor for your Z...

 

Dragonfly

[Guest jeodellx]

Dragonfly thanks for your response.

 

I know that the intermittent wiper originally worked and the wipers would return home once turned off. I had removed the kick panel to add a speaker and the wires came off the relay while it was hanging in the footwell. The relay has a four (I think) wire connector plugged in and then I have four wires ( one red, two blue, and one blue with white) that have individual spade connectors to plug onto the relay.

 

I know the PO did upgrades on this car: it has the 2.8L with 5 speed and electric fuel pump. I think the intermittent wipers are stock though, but either way if someone has a schematic for the relay I could probably figure out what wire goes to what connector.

 

I will try plugging the wires into the relay one at a time and see what works, but I don't want to kill the relay or motor.

[Dragonfly]

I will try plugging the wires into the relay one at a time and see what works, but I don't want to kill the relay or motor.

 

I doubt if you will kill the relay or motor but here is a suggestion for you. Use your multimeter (or borrow one if you don't have one) to check each of the wires. Set the meter to read DC volts then connect the black wire from the multimeter to a good ground, with the key turned to the run position check each wire with your red meter wire, write down what each wire reads. Now turn your windshield wipers to low and check each of the wires again and again write down the readings for each wire, repeat again with the wipers on high and intermitant.

 

If these wires and that relay are for the wiper motor you will have one wire that had 0 volts with the key on and the wiper switch off and 12 volts (+ or - 2 volts) when the wiper switch is turned on, you should have one that has 12 volts (+ or - 2 volts) all the time, one wire that goes to ground and one wire that seems to do nothing.

 

If you find the above to be true then the wire that had 0 volts with the key on and the wiper switch off and 12 volts (+ or - 2 volts) when the wiper switch is turned on is your power wire for your relay, the grounded wire is the ground wire for the relay (should be black), the wire that has 12 volts (+ or - 2 volts) all the time will be the power for your wiper motor (at the relay) and the one that seems to do nothing will go to your wiper motor.

 

Unfortunately from the wire colors you said you have I doubt you will get what you are hoping for. If you can try to get a picture of the relay and the wires and post it up, if I can't tell where the relay is from the picture give a detailed discription of where it is mounted as well.

 

Dragonfly

[Guest jeodellx]

Thanks Dragonfly, I'll check the wires tonight.

[Dragonfly]

I just took a look at some of my wiring diagrams and what I found is that there is a relay but my drawings show it as having a blue wire with a yellow stripe, a blue wire with a red stripe, a yellow wire and a black wire. If you have the ability to open an AutoCAD drawing I will send you the wiring diagram.

 

The diagram I found it on was for a 74' 260Z, when I looked at my diagram for a 72' 240Z it did not have this relay, I do not have a diagram for a 73' 240Z so I am guessing that you have a late 73' that has many of the 74' goodies in it.

 

Dragonfly

[Guest jeodellx]

Okay, here is what I got.

Red wire 12V constant with key on. (this wire is blue with red stripe about 4 inches from spade connector)

Black wire 12V constant with key on. (this wire is blue with white stripe about 4 inch from spade connector)

White wire is 12V with key on and then OV when intermittent wiper selected. (this wire is blue with white stripe about 4 inches from spade connector)

Blue wire is OV constant

 

I did find a schematic in a chilton manual for a 73 240Z that shows the intermittent wiper relay, it has letter designations but I can not find the letters on the relay. The book shows PMEB1BW2E, with 1 to blue, B to blue/red, W to blue/white,and 2 to blue/white. The schematic shows 9 connections total, but I only have seven wires going to relay? The relay also has 2 pins clipped off where the 4 pin connector hooks in which would make 10 pins total. With the 4 pin connector in place that leaves me with 6 to choose from.

 

Currently the wipers only work when fast is selected and this works with the four pin connector attached to the relay or not.

 

I have a few photos of the relay and wires below. The relay is on the upper left with electrical tape covering the two clipped connections.

 

Thanks again for the help

[Guest jeodellx]

update: I seem to have some connection issues, because while troobleshooting my turn signals not working I now have slow and fast wiper speed, intermittent (it only cycles once though), and the wipers cycle once when turned off and then return home. This is a definite improvement, but I still need to get the intermittent to work correctly.

[Dragonfly]

My diagram shows two connectors to the relay, one connector with three wires (which I see in the first picture) the second connector with four wires. I can see from the pictures that some one in that cars past thought they knew more than the manufacturer and cut off the connector than (probably much later) fastened some replacement wires on it to try to get it working again.

 

At this point I would recomend that you try to find a 73' thru 76' Z in a wrecking yard that has that relay and the proper factory conectors, buy the relay and the connector you are missing (with about 4" of wire). Then splice the connector back into your wiring harness making sure your wire colors match up, if your old relay is toast from abuse you have a replacement for it in your hand. Oh yeah I almost forgot to say that my diagram showed some blanked off pins on the relay.

 

Dragonfly

[Dragonfly]

update: I seem to have some connection issues, because while troobleshooting my turn signals not working I now have slow and fast wiper speed, intermittent (it only cycles once though), and the wipers cycle once when turned off and then return home. This is a definite improvement, but I still need to get the intermittent to work correctly.

 

If you go to a salvage yard like I mentioned in the post above get the entire steering wheel switch assembly while you are there. That assembly consist of the headlight switch, wiper switch and blinker switch on the opposite side. Before you get this replacement pull yours out of your car and look at the connectors on it and make a note of them, take your note with you because not all these switch assemblies have the same connectors and you want to be sure the replacement one you get has the right ones for your car.

 

Dragonfly

[Guest jeodellx]

Dragonfly,

Thanks for your help so far!

 

Does you diagram show which connections on the relay are used? I am going to start calling the J/Ys, but I think it is unlikely that I will find one around here.

[Dragonfly]

Dragonfly,

Thanks for your help so far!

 

Does you diagram show which connections on the relay are used? I am going to start calling the J/Ys, but I think it is unlikely that I will find one around here.

 

Diagramaiticaly it does but I will have to wait untill I get a chance tonight to get a look at it again. I will see if I can tell you which wire goes to which pin in the picture you have.

 

I have spent countless hours going throught the wiring on the Z cars I have owned so I know the frustration.

 

Dragonfly

[Dragonfly]

Rather than trying to explain the diagrams I just converted them so I can post them.

 

This one is from the diagram for the 74'

 

 

And this one is the diagram for the 77'

 

Hope these help.

 

Dragonfly

[Guest jeodellx]

Dragonfly,

 

Thanks again. At least the wire colors that I have look like they should go onto this relay. The problem is that the four wire plug only has three wires in it and the blue with red wire had been separated out. It has its own spade connector so I am unsure where it belongs. The relay had been opened by the pervious owner and maybe he modified it to work with this setup.

 

I have tried just plugging in the two B/W and one B wires without plugging in the B/R but there is no change in operation. Will try to locate another car for parts.

 

There are two other wiring issues that maybe you could help me with. The first is the rear defroster; it has never worked and I am wondering if you have troubleshot this circuit before and know what to look for. What type of resistance should I be getting at the rear window and what should I look for at the relay?

 

The second is a question about the stock radio. I had pulled out the dash to rebuild the heater assembly, and I did a pretty thurough job of labeling all wires, but when it was pretty obvious where something went I didn't mark it. Well I hooked everything back up and i can not locate a connector for the three pin connector that has only one wire in it with a fuse inline for the radio. I have been trying to eliminate any other three wire connector that should be left unpluged, but it seems like everything is in the correct place. Can you describe which harness the radio plugs into and how many wires and what wire colors are in the connector?

 

I really appreciate you taking the time to help me out. I am usually really good at putting things back together, but I had to let the car sit for about two years because of other priorities.

 

Jeff

[Dragonfly]

I learned a long time ago not to trust my memory to much when it comes to reassembling something that seems obvious, In the future mark everything with as much detail as possible and take digital pictures as you go. I'm not sure how much help I will be able to give you on the radio but I will look at my diagrams after I get home.

 

The rear defrost on Z cars usualy does not work because the element in the glass has been worn through by age and cleaning and therefore has opens in the circuit (usualy several of them). There are kits you can purchase that allow you to rebuild the "trace" in your window, it might be a good idea for you to research that route.

 

Dragonfly

[Guest jeodellx]

Dragonfly,

I found a 73 in a JY and it actually had the relay and wiring still installed. All the wires I have are used, but are different from the diagram you had and the schematics in my books. The four pin connector does only have three wires in it. I'll list what I found incase anyone in the future finds it useful.

 

4 pin connector (X=unused)

Y / B

X / YL

 

6 pin connector

LR / LW

L / X

Lw / X

 

The intermittent now works, but for some reason the window washer motor runs intermittently when any of the wiper speeds are selected. I have tried both relays, but have decided just to leave the washer motor unpluged for now.

 

I found where to plug in the radio; I have a plug that I think is supposed to not be plug in, because when it is the dash and running lights are on whenever the key is turned on.

 

I have decided to live without a defroster for a while longer-- I think I have had enough fun with 34 year old wiring for now.

 

Thanks again for all the help

[Dragonfly]

Your welcome. Did you get the steering column switch assembly while you were at it? If not it could be a good idea (or at least take a look at it) because the contacts do start to get a little rough after awhile.

 

Dragonfly

[Guest jeodellx]

Unfortunately the steering column was already gone. I found a bad connection on my turn signal flasher and had to rebuild my turn signal switch because of extremely slow flashing. My turn signals are still slower than I would like, especially the left turn, but at least they are working. I'm pretty sure the resistance is in the switch, because after cleaning my hazard switch the hazard flashers work at normal speed.

 

Hopefully I can find another car to get some more parts off of, doesn't seem to be very many in this area though.

 

Later,

Jeff

[Juarez88]

im going to bump this thread for a quick question.

 

would a bad relay cause windshield wipers NOT to turn off? Whenever I turn the windshield wipers on then switch them back to the off position, they won't turn off. I also hear a clicking sound ever 5 or so seconds from the relay.

 

p.s my car is also a 73' 240z.

[Guest moonbandito]

Battery grounded to firewall via battery bracket and (+) battery cable. The result was that two ground wires melted the insulation off themselves.

 

It was dramatic. The smoke from the melting insulation was substantial - and I thought I'd fried everything - the car still runs, and except for the exposed ground wires in the bundles - all looks to be OK for now.

 

I know I'll need to replace/rebuild the wire bundle running to the wiper motor, as a ground wire goes to the wiper motor and it is now 'insulation free'.

 

There seems to be another ground wire running into a larger bundle that passes through the firewall.

 

I live in SoCal (central Orange county)

 

the car is a '73 240z with the only mods being an added stereo.

 

Question: How shall I fix the problem? Any used wiring harness parts available?